Deprecate most methods which were never used in `DatabaseLimits`

`DatabaseLimits` and those methods were introduced at 3809c80, but most
methods were never used and never tested from the beginning (except
`table_alias_length`, `index_name_length`, and `in_clause_length` (since
66c09372)).

There is no reason to maintain unused those methods for about 8 years.

1 files changed, 28 insertions, 0 deletions

diff --git a/activerecord/test/cases/adapter_test.rb b/activerecord/test/cases/adapter_test.rb
index 67734d24d7..1c461a0459 100644
--- a/activerecord/test/cases/adapter_test.rb
+++ b/activerecord/test/cases/adapter_test.rb
@@ -300,6 +300,34 @@ module ActiveRecord
     def test_supports_multi_insert_is_deprecated
       assert_deprecated { @connection.supports_multi_insert? }
     end
+
+    def test_column_name_length_is_deprecated
+      assert_deprecated { @connection.column_name_length }
+    end
+
+    def test_table_name_length_is_deprecated
+      assert_deprecated { @connection.table_name_length }
+    end
+
+    def test_columns_per_table_is_deprecated
+      assert_deprecated { @connection.columns_per_table }
+    end
+
+    def test_indexes_per_table_is_deprecated
+      assert_deprecated { @connection.indexes_per_table }
+    end
+
+    def test_columns_per_multicolumn_index_is_deprecated
+      assert_deprecated { @connection.columns_per_multicolumn_index }
+    end
+
+    def test_sql_query_length_is_deprecated
+      assert_deprecated { @connection.sql_query_length }
+    end
+
+    def test_joins_per_query_is_deprecated
+      assert_deprecated { @connection.joins_per_query }
+    end
   end
 
   class AdapterForeignKeyTest < ActiveRecord::TestCase